Moderna’s stock retreated on Thursday following a record-setting jump a day earlier, cutting more than $18 billion from the company’s market valuation, as investors appeared to pull back after the biotech giant reported breakthrough trial results for a cancer vaccine.

Shares of Moderna plunged more than 25% to around $129 as of early Thursday afternoon, a retreat from the firm’s record-setting 176% surge Wednesday that more than doubled the stock’s value, to above $174.

Skyrocketing shares followed Moderna's announcement that its personalized cancer drug—an mRNA-based shot combined with Merck’s immunotherapy drug Keytruda—helped reduce the recurrence of melanoma and significantly extended the time patients lived without their melanoma returning.

A decline appears to represent investors taking profits from the stock surge, and Wall Street still applauded Moderna’s trial results: Bank of America analyst Alec Stranahan, who more than quadrupled his share price target for Moderna to $170 from $40, called the results a “watershed moment” for the firm, allowing it to further diversify from infectious disease.

Stranahan noted we “still don’t know how much better” Moderna’s combined drug is than Keytruda alone, and that more testing would likely be necessary.

$51.5 billion. That’s Moderna’s market valuation as of Thursday, marking a more than $18 billion decline from Wednesday’s closing valuation of $69.6 billion.

Moderna’s record-setting stock surge made co-founder Thomas Langer a billionaire once again, raising his roughly 3% stake in the firm from $730 million on Tuesday to about $1.7 billion on Wednesday. Fellow co-founder Noubar Afeyan’s net worth jumped $184 million to $2.2 billion, and CEO Stéphane Bancel’s fortune rose $2.5 billion to $5.8 billion. Afeyan’s net worth fell $105 million to $2.1 billion on Thursday, and Bancel’s fell by $1.3 billion to $ 4.4 billion.

Leerink Partners analyst Mani Foroohar wrote in June that Moderna’s late-stage cancer vaccine trial would be a make-or-break event for its stock, with the potential for the experimental drug to work across multiple types of cancer. Merck and Moderna have said they are looking into several trials of the vaccine for other cancers, including non-smallcell lung cancer and bladder cancer. Moderna’s business boomed from the success of its mRNA-based COVID-19 vaccine, though it posted a net loss of $782 million on revenue of $145 million through its latest quarter.

Moderna Shares Skyrocket 125% Toward Best Day Ever—On Success Of Cancer Drug Trial ( Forbes )

Moderna Co-Founder Robert Langer Is A Billionaire Again As Shares Double In Value ( Forbes )